Wind resource is a kind of inexhaustible and incessant energy resource. The utilization of wind in power generation may reduce environmental pollution and save conventional energy resources such as coal and oil. The wind power generation technology is mature, with relatively low cost among renewable energy resources and broad prospect for development. The wind power generation technology may be applied flexibly. It can operate not only on-grid collaboratively but also off-grid independently, and it may also form complementary power generation systems with other energy technologies. However, torque is generally transmitted between blades and rotors of the existing wind generators by rotating shafts or gear mechanisms, a high wind speed of typically 3.5 m/s is often required to start up the existing wind power generators, and the application of the existing wind power generators is limited largely.